Electrical connecting apparatus

ABSTRACT

An electrical connecting apparatus is characterized by inserting a first pin having a flange portion into a through hole of an elastic body via a seat, by disposing a second pin in the through hole so as to adjoin in the axial direction of the through hole relative to the first pin, and by bringing the first and second pins into contact in a plane region having a certain angle to the axis of the through hole.

CROSS-REFERENCE TO RELATED APPLICATION

This Application claims priority from International Application NumberPCT/JP03/001381, titled “Electrical Connecting Apparatus,” filed Feb.10, 2003.

FIELD OF ART

The present invention relates to an electrical connecting apparatus foruse in an electric test of a plate-like device under test such as asemiconductor device.

BACKGROUND OF ART

An electric test of a plate-like device under test provided with aplurality of electrodes such as a semiconductor device is generallyconducted, using an electric connecting apparatus such as a probe card,a probe unit, a probe block and the like.

As one of such electric connecting apparatus, there is a type providedwith a cylindrical elastic body and a first and a second contact pinsdisposed in a through hole portion of this elastic body (Patent Document1).

Patent Document 1:

Japanese Patent Appln. Public Disclosure No. 2001-250600

In this conventional apparatus, the first and second pins are disposedto adjoin each other in the axial direction of the through hole portionand come in contact in an inclined plane inclined to the axis of thethrough hole portion, and the apparatus is further provided with aflange-like base, which is in contact with a face of an elastic plate,at an end portion on the opposite side to the inclined plane.

In this conventional apparatus, when energizing force is exerted in adirection to make the first and second pins approach each other, bothpins displace along the inclined plane with which they are in contact tocompress and deform the elastic body in the axial direction of thethrough hole, deforming the through hole in a direction to expand, andwhen the energizing force is no longer exerted on the first and secondpins, the pins are restored to their initial state by the elastic forceof the elastic body.

In the above-mentioned conventional electrical connecting apparatus,however, though the elastic body is elastically deformed in the axialdirection when the energizing force is exerted on the first and secondpins, a part which compresses and deforms the elastic body in its axialdirection is merely the flange-like base. Therefore, the forcecompressing and deforming the elastic body in its axial direction isgreatly counteracted by the force expanding the through hole, so thatthe amount of compression and deformation of the elastic body due to theenergizing force is remarkably small. Also, the force to compress anddeform the elastic body in its axial direction falls short.

Also, in the foregoing conventional electrical connecting apparatus,when the energizing force is no longer exerted on the first and secondpins, the force which has compressed and deformed the elastic body inthe direction to expand the through hole acts as frictional resistanceforce to the first pin which tends to return to the axial direction ofthe through hole. For this reason, restoring force acting on the firstpin due to the force which has compressed and deformed the elastic bodyin the axial direction of the through hole is greatly counteracted bythe restoring force acting on the first pin due to the force which hasexpanded the through hole.

As a result, in the conventional electrical connecting apparatus, whenthe energizing force no longer acts on the first and second pins, therestoring force for returning the first and second pins to their initialstates, more particularly, the force for displacing the first pin in adirection to be apart from the second pin falls short.

SUMMARY OF THE INVENTION

The electrical connecting apparatus according to the present inventioncomprises: a plate-like elastic body with a plurality of first throughholes penetrating the elastic body in its thickness direction; aplurality of elastically deformable seats having second through holesindividually corresponding to said first through holes and arranged inthe elastic body, each second through hole penetrating said seat in itsthickness direction and being communicated to the corresponding firstthrough holes; a plurality of first pins, each provided with a firstportion received in the first and second through holes, a second portionprojected from the second through hole, and a flange portion which iscapable of contacting with the seat; and a plurality of second pinsreceived in the first through holes so as to adjoin in the axialdirection of the first through holes relative to the first pins. Atleast one of the first and second pins further include on the other sidea plane region having an angle to the axis of the first through holes,the other of the first and second pins include on the other sidepositions capable of contacting the plane region.

The electrical connecting apparatus is used, for example, with theelastic body assembled into a wiring base plate such that the firstthrough holes are individually opened into a plurality of connectionlands. At the time of an electrical test, an electrical connectingapparatus and a plate-like device under test such as a semiconductordevice are relatively pressed such that an electrode of the device undertest is brought into contact with the end portion on the first portionside of the first pin.

By this, the first pin presses the second pin, so that the first andsecond pins are relatively displaced. As a result, while elasticallydeforming the corresponding seat, the first pin is displaced at least inthe axial direction of the first through hole to compress and deform theelastic body by the flange portion via the seat in the thicknessdirection. On the other hand, the second pin compresses and deformsmainly the first through hole in a direction to expand the first throughhole, because the plane region has an angle to the axis of the firstthrough hole.

At the time of the above-mentioned deformation by compression, sinceforce to compress the elastic body in its thickness direction acts onthe elastic body through the seat, the force is greater than when theelastic body is directly deformed by the flange portion and a case wherethe first through hole is expanded by the first pin.

When pressure against the first and second pins is released, the firstand second pins are restored to their initial states by the elasticforce (restoring force) of the elastic body. At this time, the first pinis guided by the seat mainly in the axial direction of the first throughhole, and the force to make the first pin return in the axial directionof the first through hole acts on the flange portion through the seat.Furthermore, the frictional resistance between the first pin and theelastic body when the first pin returns in the axial direction of thefirst through hole is remarkably small, because the force for the firstpin to compress and deform the elastic body so as to expand the firstthrough hole is small, compared with the conventional apparatus.

As a result, according to the present invention, the compressive forceto compress and deform the elastic body and the restoring force toreturn the first pin in the axial direction of the first through holebecome greater than the conventional apparatus, and the first and secondpins surely return to their initial states.

The electrical connecting apparatus can further comprise a wiring baseplate provided with a plurality of connection lands individuallycorresponding to the first through holes, wherein each first throughhole is opened individually in the connection land. By doing so, theelastic body can be assembled into the wiring base plate.

The second pin may have the end portion opposite to the first pin formedas a spherical plane and may be brought into contact with the connectionland at a part of the spherical plane. By doing so, when the first andsecond pins are relatively pressed, since the second pin is pressedagainst the connection land, and since the first and second pins are incontact in the plane region intersecting the axis of the first throughhole, the second pin is easily inclined along the spherical plane, sothat the first pin tends to be easily displaced in the axial directionof the first through hole.

Both first and second pins may be provided with the plane region. Bydoing so, when the first and second pins are relatively pressed, thecontact area of the first and second pins is increased, so that theelectrical contact resistance of the first and second pins is decreased.Also, when the first and second pins are relatively pressed and when thepressure is released, the first pin is surely displaced in the axialdirection of the first through hole.

The plane region of either one of the first and second pins may have aconvex cross sectional shape, and the other plane region may have aconcave cross sectional shape into which the one plane region is fittedso as to relatively displace. By doing so, the first and second pins isprevented from relatively displacing in the cross-sectional direction.

The plural seats may be integrally formed with a seat-like member havingthe second through holes and laid on the elastic body. This facilitatespositioning of the seats and the elastic body, and the first pin, beingguided to the second through hole, is surely displaced mainly in theaxial direction of the first through hole.

In order to make seat-like regions around adjoining second through holesas the seats, the seat-like member can be further provided with aplurality of slits for dividing so that those seat-like regions continuepartially. By doing so, when the first and second pins are relativelypressed and when the pressing is released, each seat-like region isindependently surely deformed, so that the first pin is surely moved inthe axial direction of the first through holes.

The electrical connecting apparatus can further comprise a presser platelaid on the seat, wherein the presser plate can be provided with aplurality of holes individually receiving the second portions of thefirst pins with their tip portions projected, and a plurality ofrecesses communicated to the holes and individually receiving the flangeportions. This prevents falling of the first pins from the first andsecond through holes.

The first pin can be further provided with one or more pyramidalprojections projecting further from the second portion. By doing so, theelectrode of the device under test and the first pin are surely broughtinto contact.

The elastic body can be further provided with a recess around the firstthrough hole and opening on the side of the seat. Thereby, when thefirst and second pins are relatively pressed, the second pin is easilyinclined, so that it becomes easy for the first pin to be displaced inthe axial direction of the first through hole.

The second pin may have not only the plane region but also an L-shapedstage portion in the lower part of the plane region, and the elasticbody may further have a presser portion projected within the firstthrough hole and for pressing the second pin at the stage portion, andthe first pin and the stage portion may have a space where the first pinescapes when the first and second pins are relatively pressed formedinside the first through hole and above the presser portion. Thisenables to increase an over drive amount to be acted on the device undertest and raise a contact pressure of the first and second pins as wellas the contact pressure of the second pin and the connection land, sothat the electrical contact resistance at those contact positions can bedecreased.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view showing one embodiment of the electricalconnecting apparatus according to the present invention, with the wiringbase plate omitted.

FIG. 2 is a section obtained along the line 2—2 in FIG. 1.

FIG. 3 is a plan view of the electrical connecting apparatus shown inFIG. 1, with the frame and the presser plate removed.

FIG. 4 is a plan view of the electrical connecting apparatus shown inFIG. 1, with the frame, the presser plate and the seat member removed.

FIG. 5 is an exploded perspective view of members other than the wiringbase plate of the electrical connecting apparatus shown in FIG. 1.

FIG. 6 is a perspective view for explaining one embodiment of the methodof producing the elastic body and the lattice in the electricalconnecting apparatus shown in FIG. 1.

FIG. 7 is a plan view of the neighborhood of the first and second pinsin the electrical connecting apparatus shown in FIG. 1.

FIG. 8 is a perspective view of the pins showing one embodiment of thefirst and second pins used in the electrical connecting apparatus shownin FIG. 1.

FIGS. 9A and 9B are vertical sections showing the neighborhood of thefirst and second pins for explaining the motion of the electricalconnecting apparatus shown in FIG. 1, in which FIG. 9A shows a statewhen an over drive is not acted and FIG. 9B shows a state when an overdrive is acted.

FIGS. 10A and 10B are views showing part of another embodiment of theelectrical connecting apparatus, in which FIG. 10A is a plan view andFIG. 10B a vertical section.

FIGS. 11A and 11B are views showing part of the other embodiment of theelectrical connecting apparatus, in which FIG. 11A shows a state when anover drive is not acted and FIG. 11B a state when an over drive isacted.

FIGS. 12A, 12B, 12C and 12D are cross sections respectively showingvarious embodiments of the plane regions of the first and second pins.

DETAILED DESCRIPTION

Referring to FIGS. 1 through 9, the electrical connecting apparatus 10is used to electrically connect a device under test 12 and testers in anelectrical test as to whether a semiconductor device, particularly theplate-like device under test 12 such as an integrated circuit functionsor not as per specification.

The device under test 12 has a plurality of projected electrodes 14having a semispherical shape like a solder bump arranged in a matrixstate on the plate-like base 16 having a rectangular shape. Eachprojected electrode 14 is electrically connected to the circuit withinthe base 16.

The electrical connecting apparatus 10 comprises a plurality of firstpins 20, a plurality of second pins 22 corresponding to the first pins20 in one-to-one relationship, a wiring base plate 24, an elastic body26 laid on the wiring base plate 24, a lattice 28 disposed within theelastic body 26, a seat-like member 30 laid on the elastic body 26, apresser plate 32 laid on the seat-like member 30, and a rectangularframe 34 laid on the presser plate 32.

Each first pin 20 is provided, as shown in FIGS. 8 and 9, with arod-like first portion 36, a second portion 38 integrally following theupper end of the first portion 36, a plurality of pyramidal projections40 integrally formed at the upper end of the second portion 38, and aflange portion 42 integrally formed in the periphery of the lower end ofthe second portion 38.

The first and second portions 36 and 38 have the same diametraldimension. The plural projections 40 are spaced apart about the axis ofthe first pin 20 so as to act as contact portions to contact theprojected electrodes 14 and make the top portions project toward theside opposite to the first portion 36.

Each of the second pins 22 has, as shown in FIGS. 8 and 9, substantiallythe same diametral dimension as the first and second portions 36 and 38of the first pin 20 with its lower end portion formed as a sphericalplane. The first and second pins 20 and 22 are disposed to adjoin intheir axial direction with their axes coincided, and make the adjoiningportions plane regions 46 and 48 capable of contacting each other.

The plane regions 46 and 48 are inclined at a predetermined angle θrelative to the axes of the first and second pins 20 and 22. The angle θcan be 60° or less, preferably 45° or less, and more preferably 30°.

The wiring base plate 24 has, as shown in FIG. 2, a plurality ofconnection lands 50 individually corresponding to a pair of the firstand second pins 20 and 22, and a plurality of lands 52 for groundinglocated between adjacent connection lands 50 on one face (the upperface) in the thickness direction. The connection lands 50 and groundinglands 52 are formed by a publicly known technique such as printed wiringtechnique.

The elastic body 26 is made of an electrically insulating rubbermaterial such as silicone rubber so as to deform in three dimensionallyby compression and has a plurality of through holes 54 individuallycorresponding to the pair of the first and second pins 20 and 22. Thethrough holes 54 penetrate the elastic body 26 in its thicknessdirection. The first and second pins 20 and 22 are disposed in thethrough holes 54 so as to be vertically adjacent to each other with thespherical plane 44 of the second pin 22 brought into contact with thecorresponding connection lands 50.

The lattice 28 is made of a conductive metal material. In theillustration, the lattice 28 has, as shown in FIGS. 2, 4, 5 and 6, aplurality of strip-like members 56 having substantially the same widthdimension as the thickness dimension of the elastic body 26 andconductivity and combined vertically and laterally so as to partition anelastic region around each hole 54 of the elastic body 26 from adjoiningelastic regions, making their width direction the thickness direction(vertical direction) of the elastic body 26.

Each strip-like member 56 has, as shown in FIG. 6, a plurality of holes58 which make adjoining elastic regions partially continue. The lattice28 may be, however, produced as one unit with the plural strip-likemembers 56 integrally combined vertically and laterally, and a hole 58may not necessarily be formed in the strip-like member 56.

As shown in FIG. 6, the lattice 28 can be disposed inside the elasticbody 26 with a plurality of strip-like members 56 vertically andlaterally combined within a case-like form 60 opening upward, casting arubber material into the form 60 up to a predetermined depth so that thestrip-like members are not immersed, and hardening the rubber material.

The lattice 28 produced as above exposes both end faces in the widthdirection of each strip-like member 56 out of the elastic body 26. Anintegrated body of the elastic body 26 and the lattice 28 is laid on theupper face of the wiring base plate 24 such that the through hole 54 inthe corresponding connection land 50 is opened, and that one end face inthe width direction of each strip-like member 56 is brought into contactwith at least one grounding land 52 (see FIG. 2).

The seat-like member 30 is made of an electrically insulating resin ormetal, preferably a resin such as polyimide. As shown in FIGS. 2 and 3,the seat-like member 30 has a plurality of through holes 62 penetratingthe seat-like member 30 in its thickness direction, and a plurality ofslits 64 for dividing seat-like regions 63 around the adjoining throughholes 62 such that the seat-like regions 63 continue partially.

Each seat-like region 63 of the seat-like member 30 is broader than theflange portion of the first pin 20 and acts as a seat.

Each through hole 62, made to correspond to the through hole 54, opensin the corresponding through hole 54. Each seat-like region 63corresponds to the elastic region of the elastic body 26 in one-to-onerelationship. The seat-like member 30 is laid on the elastic body 26 andthe lattice 28 such that each through hole 62 is opened in thecorresponding through hole 54 and that each slit 64 opposes thestrip-like member 56.

The presser plate 32 is, like the seat-like member 30, made of anelectrically insulating resin or metal. The presser plate 32 has aplurality of holes 66 for individually receiving the second portion 38of the first pin 20 such that its tip is projected, and a plurality ofrecesses 68 individually receiving the second portion 38 of the firstpin 20 such that the tip portion of the first pin 20 is projected, and aplurality of recesses 68 individually receiving the flange portions 42individually communicated to the holes 66.

Each hole 66 and each recess 68 are made coaxial and made to correspondto the through hole of the seat-like member 30 in one-to-onecorrespondence. The presser plate 32 is laid on the seat-like member 30such that each hole 66 and each recess 68 are coaxial with the throughhole 62.

The frame 34 is provided with a rectangular opening 70 having adimension capable of receiving the base 16 of the device under test 12.Among the inner faces forming the opening 70, the upper part is made adiagonally upward inclined face 72 for guiding the device under test 12correctly to the center side of the opening 70. The frame 34 is laid onthe presser plate 32 so that all the first pins 20 may enter the opening70 as viewed in plane.

The first portion 36 of the first pin 20 is inserted into the throughhole 62 of the seat-like member 30 and the through hole 54 of theelastic body 26 such that the plane region 46 is downward, that thesecond portion 38 penetrates the hole 66 of the presser plate 32 toproject upward, and that the flange portion 42 is received in the recess68 of the presser plate 32.

The second pin 22 is inserted into the through hole 54 of the elasticbody 26 such that the plane region 48 comes above to oppose the planeregion 46 of the first pin 20. The diametral dimensions of first portion36 of the first pin 20 and the second pin 22 can be substantially thesame as the diametral dimensions of the through holes 54 and 62. As aresult, both plane regions 46 and 48 are brought into contact in plane,and the spherical plane 44 of the second pin 22 is in contact with theconnection land 50.

To arrange the first and second pins 20 and 22 as mentioned above, it ispossible, for example, to lay the elastic body 26 on the wiring baseplate 24, lay the seat-like member 30 on the elastic body 26 such thatthose overlapped members are positioned by passing a plurality ofpositioning pins 74, and then, pass the first portion 36 of the firstpin 20 into the through holes 54 and 62, and thereafter, and then, passthe positioning pins 74, insert the second pin 22 into the through hole54 into the presser plate 32 to lay the presser plate 32 on theseat-like member 30.

As a result, the first and second pins 20 and 22 are arranged in alaminated substance in which the seat-like member 30 and the presserplate 32 are laminated, so that they are prevented from falling out ofthe through holes 54 and 62.

The electrical connecting apparatus 10 is, thereafter, laid on theoverlapped substance by passing the positioning pins 74 through theframe 34, and the wiring base plate 24, the elastic body 26, theseat-like member 30, the presser plate 32 and the frame 34 are combinedby a plurality of screw members 76 so as to be capable of disassembling,thereby facilitating the assembling.

Where the positioning pins 74 are assembled into the wiring base plate24, the positioning pins 74 are received in the holes of the elasticbody 26, the wiring base plate 24 and the seat-like member 30 such thatfirstly the elastic member 26 overlaps the wiring base plate 24, and theseat-like member 30 is laid on the elastic body 26, and then, the firstand second pins 20 and 22 are arranged as mentioned above, andthereafter, the positioning pins 74 are received into the holes of thepresser plate 32 such that the presser plate 32 are laid on theseat-like member 30, thereby resulting in the overlapped substance.

Thereafter, the positioning pins 74 are received in the holes of theframe 34 so that the frame 34 and the overlapped substance may overlap,and finally, the laminated substance and the frame 34 are combined by aplurality of screw members 76.

The electrical connecting apparatus 10 is disposed in a testingapparatus such that the axial direction of the through holes 54 and 62becomes the vertical direction. In that state, firstly the device undertest 12 is disposed in the opening 70 of the electrical connectingapparatus 10 with the projected electrode 14 located downward. At thistime, the first and second pins 20 and 22 are, as shown in FIG. 9A,maintained such that their axes extend vertically.

Next, the device under test 12 and the electrical connecting apparatus10 are pressed in the direction to approach each other. By this, theprojected electrode 14 and the pyramidal projection 40 are pressed, sothat the projected electrode 14 and the first pin 20 are surely broughtinto electrical contact.

When the projected electrode 14 and the first pin 20 are pressed, thefirst pin 20 presses the second pin 22, thereby displacing the first andsecond pins 20 and 22 relatively. As a result, the elastic body 26 andseat-like member 30 are surely elastically deformed because the elasticregion and the seat-like region 63 around the adjoining through holes 54and 62 are respectively deformed independently.

Also, when the projected electrode 14 and the first pin 20 are pressed,since the plane regions 46 and 48 are inclined to the axis of thethrough hole 54, each first pin 20 is guided into the through hole 62 ofthe seat-like member 30, and the seat-like region 63 is separated by theslit 64, each first pin 20 is, as shown in FIG. 9B, surely displacedmainly in the axial direction of the through hole 54, and the seatregion 63 is elastically deformed by the flange portion 44, therebycompressing and deforming the elastic region 63 of the elastic body 26in the thickness direction.

On the other hand, the second pin 22, in which the plane regions 46, 48are inclined to the axis of the through hole 54 and the spherical plane44 is pressed against the connection land 50, is inclined, as shown inFIG. 9 (B), along the spherical plane 44, so that the elastic region ofthe elastic body 26 is compressed and deformed mainly in a direction toexpand the through hole 54.

At the time of compression and deformation as mentioned above, since theforce to compress the elastic body 26 in its thickness direction acts onthe elastic body 26 through the seat-like member 30 and the elasticregion of the elastic body 26 and the seat region 63 of the seat-likemember 30 are independently deformed, the force is remarkably great incomparison with the case of directly deforming the elastic body 26 bythe flange portion 42 and the case of expanding the through hole 54 bythe first pin 20.

In the above-mentioned state, the device under test 12 is electrified.At this time, the connection land 50 is connected to a signal line ofthe tester, and the grounding land 52 is connected to the earth.

At the time of an electric test, since the first and second pins 20 and22 are pressed in the plane regions 46 and 48 inclined to the axis ofthe through hole 54, a contact area of the first and second pins 20 and22 becomes large, and the electrical contact resistance of the first andsecond pins 20 and 22 is small.

During the electric test, since each pair of the first and second pins20 and 22 is shielded by the strip-like member 56 around the pins andelectrically connected to the grounding land 52, a noise is restrainedfrom mixing in the first and second pins 20 and 22.

When the device under test 12 is removed and the pressing of the firstand second pins 20 and 22 are released, the first and second pins 20 and22 are restored to the initial state by the elastic force of the elasticbody 26.

At this time, the elastic body 26 and seat-like member 30, in which theelastic regions around the through holes 54 and 62 and the seat-likeregion 63 are respectively independently deformed, are surely restoredto the initial state to surely restore the first and second pins 20 and22 to the initial state.

Also, since the plane regions 46 and 48 are inclined to the axis of thethrough hole 54 and each first pin 20 was guided to the through hole 62of the seat-like member 30, each first pin 20 is surely displaced mainlyin the axial direction of the through hole 54.

Furthermore, the force to return the first pin 20 to the axial directionof through hole 54 surely acts on the flange portion through theseat-like member 30, and the frictional resistance between the first pin20 and the elastic body 26 when the first pin returns to the axialdirection of the through hole 54 is remarkably small in comparison witha conventional apparatus.

As mentioned above, according to the electrical connecting apparatus 10,the compressing force to compress and deform the elastic body 26 to theaxial direction of the through hole 54 and the restoring force to returnthe first pin 20 to the axial direction of the through hole 54 becomegreat in comparison with the conventional apparatus, so that the firstand second pins 20 and 22 are surely restored to the initial states.

As shown in FIG. 10, the elastic body 26 may further have an arc-shapedrecess 78 around the through hole and opening on the side of the shieldmember 30. If the recess 78 is formed in the elastic body 26, the secondpin 22 is liable to incline to the axis of the through hole 54 when thefirst and second pins 20 and 22 are pressed relatively, so that itbecomes easy for the first pin 20 to be displaced in the axial directionof the second pin 22.

As shown in FIG. 11, it is possible to cut the second pin 22 in anL-letter shape at the lower part of its plane region 48, to form anupward stage portion 80 in the second pin 22, to form in the elasticbody 26 a presser portion 82 projecting from the elastic body 26 intothe through hole 54 to press the second pin 22 in the stage portion 80,and to form a space 84 acting as an escape portion of the first pin 20above a presser portion 82 just in case the first and second pins 20 and22 are relatively pressed.

As mentioned above, if the stage portion 80 and the presser portion 82are respectively provided in the second pin 22 and the elastic body 26,the elastic region of the elastic body 26 is greatly compressed anddeformed, and the second pin 22 is strongly pressed against theconnection land 50.

As a result, it is possible to raise the contact pressure of the firstand second pins 20 and 22 as well as the contact pressure of the secondpin 22 and the connection land 50 by increasing the over drive amountand to reduce the electrical contact resistance of them at their contactportions.

It is possible to shape the plane regions 46 and 48 as follows. It isalso possible to form a plane region in either one of the first andsecond pins and to form in the other of them a convex portion in contactwith the plane region.

As shown in FIG. 12A, both plane regions 46 and 48 may be flat planes.

As shown in FIG. 12B, however, it is possible to make one plane region46 a convex plane region having a cross-section somewhat bent at thecenter and the other a concave plane region having a cross-section bentlikewise to be fitted on the convex plane region so as to bedisplaceable as mentioned above.

Also, as shown in FIG. 12C, it is possible to make one plane region 46 aconvex plane region having a one-side open rectangular cross-sectionalshape into which a convex plane region as mentioned above is fitted, andthe other a concave plane region having a one-side open rectangularcross-sectional shape into which the convex plane region such as aboveis fitted so as to be relatively displaceable.

Furthermore, as shown in FIG. 12D, it is possible to make the one planeregion 46 a convex plane region having an arcuate cross-sectional shape,and the other a flat plane region partially in contact with a convexplane region such as above.

If the plane regions 46 and 48 are made plane regions having suchcross-sectional plane regions as shown in FIGS. 12B and 12C, the firstand second pin 20 and 22 are prevented from relatively displacing in thecross-sectional direction.

In place of forming the seat region 63 acting as a seat by forming aslit 64 in the seat-like member 30, it is possible to use respectivecontinuous integral seat regions as seats without forming any slit 64 inthe seat-like member 30. It is also possible to make the seat regions asindependent seats by completely separating them.

The present invention may be used in a state that the electricalconnecting apparatus 10 comes either on the upper side or the lower sideof the device under test 12, or may be used in a state that theelectrical connecting apparatus 10 is slanted. Also, the presentinvention can be applied to another type of electrical connectingapparatus of a flat plate-like device under test such as a liquidcrystal display panel.

The present invention is not limited to the foregoing embodiments butcan be variously modified without departing from its spirit.

1. An electrical connecting apparatus comprising: a plate-like elasticbody with a plurality of first through holes penetrating the elasticbody in its thickness direction; a plurality of elastically deformableseats having second through holes individually corresponding to saidfirst through holes and arranged in the elastic body, the seats beinglaid on one face thereof in its thickness direction, each second throughhole penetrating said seat in its thickness direction and beingcommunicated to the corresponding first through holes; a plurality offirst pins, each provided with a first portion received in said firstand second through holes, a second portion projected from said secondthrough hole, and a flange portion which is capable of contacting withsaid seat; and a plurality of second pins received in said first throughholes so as to adjoin in an axial direction of said first through holesrelative to said first pins; wherein said first and second pins arefurther provided with plane regions having an angle to the axialdirection of said first through holes, said plane regions being incontact with each other.
 2. An electrical connecting apparatus asclaimed in claim 1, further comprising a wiring base plate provided witha plurality of connection lands individually corresponding to said firstthrough holes, said wiring base plate being laid on the other face ofsaid elastic body in its thickness direction, wherein each first throughhole is opened individually in said connection land.
 3. An electricalconnecting apparatus as claimed in claim 2, wherein said second pin hasthe end portion on the side opposite to said first pin made a sphericalplane and is brought into contact with said connection land at a part ofsaid spherical plane.
 4. An electrical connecting apparatus as claimedin claim 1, wherein either one of said plane regions of said first andsecond pins has a convex cross-sectional shape, and the other planeregion has a concave cross-sectional shape into which said one planeregion is fitted relatively displaceably.
 5. An electrical connectingapparatus as claimed in claim 1, wherein said plurality of seats areintegrally formed with a seat-like member having said second throughholes and laid on said elastic body.
 6. An electrical connectingapparatus as claimed in claim 5, wherein said seat-like member isfurther provided with a plurality of slits for dividing seat-likeregions around adjoining second through holes so as to act as said seatsso that the seat-like regions may partially continue.
 7. An electricalconnecting apparatus as claimed in claim 1, further comprising a latticedisposed inside said elastic body so as to partition into the elasticregions around adjoining first through holes.
 8. An electricalconnecting apparatus as claimed in claim 7, wherein said latticeincludes a plurality of strip-like members partitioning into saidelastic regions so that said elastic region may partially continue. 9.An electrical connecting apparatus as claimed in claim 1, furthercomprising a presser plate laid on said plural seats so as to sandwichsaid plural seats in cooperation with said elastic body, said presserplate including a plurality of holes which individually receive thesecond portions of the first pins to project their tip portions, and aplurality of recesses communicated to said holes and individuallyreceiving said flange portions.
 10. An electrically connecting apparatusas claimed in claim 1, wherein said first pin is further provided withat least one pyramidal projections projecting further from said secondportion.
 11. An electrically connecting apparatus as claimed in claim 1,wherein said elastic body is further provided with a recess around saidfirst through hole and opening on the side of said seat.
 12. Anelectrical connecting apparatus comprising: a plate-like elastic bodywith a plurality of first through holes penetrating the elastic body inits thickness direction; a plurality of elastically deformable seatshaving second through holes individually corresponding to said firstthrough holes and arranged in the elastic body, each second through holepenetrating said seat in its thickness direction and being communicatedto the corresponding first through holes; a plurality of first pins,each provided with a first portion received in said first and secondthrough holes, a second portion projected from said second through hole,and a flange portion which is capable of contacting with said seat; anda plurality of second pins received in said first through holes so as toadjoin in the axial direction of said first through holes relative tosaid first pins; wherein at least one of said first and second pins isfurther provided on a side with a plane region having an angle to theaxis of said first through hole, and wherein the other of said first andsecond pins is provided with a portion capable of contacting said planeregion, said second pin being provided with said plane region and anL-shaped stage portion in the lower part of said plane region, whereinsaid elastic body is further provided with a presser portion projectinginto said first through hole and pressing said second pin at said stageportion, said first pin and said stage portion forming, in said firstthrough hole and above said presser portion, a space to serve as anescape for said first pin when said first and second pins are pressedrelatively.
 13. An electrically connecting apparatus as claimed in claim1, wherein said second pin is provided with an L-shaped stage portion inthe lower part of said plane region, and wherein said elastic body isfurther provided with a presser portion projecting into said firstthrough hole and pressing said second pin at said stage portion, saidfirst pin and said stage portion forming, in said first through hole andabove said presser portion, a space to serve as an escape for said firstpin when said first and second pins are pressed relatively.